Census figures released Thursday put the city's 2010 population at 8,175,133, a 2.1 percent increase from 2000. The statewide figures showed Buffalo and other large cities upstate continuing to lose population.
The city tally was challenged immediately as inaccurate by New York City Mayor Michael Bloomberg, who said he believed the count overlooked many recent immigrants to the city.
"We are concerned that there has been a considerable undercount," he said, adding that the city's own demographic analysis suggested there were another 225,000 people in the Big Apple.
For evidence, he pointed at the tallies for Brooklyn and Queens.
Both of those boroughs have been part of the city's residential construction boom, but the census found growth flat, with a 1.6 percent increase in Brooklyn and nearly zero change in Queens.
"It doesn't make any sense," the mayor told reporters at a news conference. He said the city added about 170,000 new housing units over the past decade, and it was "totally incongruous" that the census recorded a population increase of only 167,000.
The 2010 numbers will be used by officials drawing New York's legislative districts for the next decade. New York's current 29-member House delegation will drop to 27, its lowest level since 1823. The U.S. Census Bureau in December previously reported that the state's population grew by 2 percent in the past decade to 19.4 million.
New York City and the adjacent suburban counties to the north and on Long Island all posted growth since 2000. In contrast, the largest cities in upstate New York posted losses. Buffalo lost 10.7 percent of its population for a count of 261,310; Rochester lost 4.2 percent to 210,565; Syracuse lost 1.5 percent to 145,170.
A number of upstate areas have grappled with the slow but steady loss of people - especially college-educated young people - to warmer and more bustling areas in the South and West. Buffalo, for instance, boasted 580,000 people in 1950, meaning the city lost more than half its population in 60 years.
Overall, the 53 counties comprising upstate New York grew by 1.5 percent, with some parts of the Hudson Valley posting strong gains. The city of Albany grew by 2.3 percent to 97,856.
Robert Ward, director of fiscal studies at the Nelson A. Rockefeller Institute of Government, said it was troubling to see the declines in western New York counties like Erie and Niagara, though he noted that gains were posted elsewhere upstate, such as Monroe and Montgomery counties.
"It's good to see some upstate growth," Ward said in an email, "but in relative terms, the region continues to decline."
Bloomberg said he believed Census workers had failed to properly count the number of people living in buildings that are home to many recent immigrants.
That point was echoed by Mitchell Moss, a New York University urban planning professor, who said the census always undercounts New York City with its mix of immigrants, young people and night dwellers.
"The census always undercounted New York because it takes a lot of leg work to walk up six stories and count how many people are in an apartment," Moss said.
New York City officials also assailed the accuracy of the census after the count in 2000, and had publicly campaigned for greater public participation in the 2010 tally. Historically, many New Yorkers have ignored the census. About 60 percent of the households that received a census form mailed it back, compared to a national average of 74 percent.
Brooklyn Borough President Marty Markowitz said he found it impossible to believe the census figures. He said the growth of the borough's large communities of Hasidic Jews, for example, didn't seem to be reflected.
"I'm flabbergasted by these numbers," he said. "I know they've made a big, big mistake."
